For a long time, the epitome of luxury bedding was extra-long staple cotton, which rendered sheets soft and silky. Brands like Brooklinen and Parachute made a business of selling high-end cotton sheets at reasonable prices. But over the last few years, customers have been asking for a decidedly different type of sheet: linen. This fabric is rougher and stiffer than cotton and tends to look rumpled on the bed, which is the opposite of the smooth look you get with cotton.

Vicki Fulop, the cofounder of Brooklinen, which just launched a line of linen sheets today, says that part of the trend has to do with customers wanting to change their sheets depending on the season. Linen works better in the summer because it stands up to humidity. “It cools and insulates better because its moisture-wicking,” she explains.

Fulop says the brand spent two years iterating the linen fabric they used to ensure it had both the cooling properties that the customer wanted but also a soft hand-feel.